With the development of display manufacturing technology, liquid crystal display technology has been rapidly developing, and liquid crystal displays have been gradually replacing conventional Cathode Ray Tube displays to become the mainstream of future flat panel displays. In the field of liquid crystal display technology, TFT-LCDs (Thin Film Transistor Liquid Crystal Displays) are widely used in the fields of television, computer, mobile phone and the like due to the advantages of large size, high integration, powerful function, flexible process, low cost and the like.
In an ADS mode (Advanced Super Dimension Switch mode) display panel, an electric field generated between edges of slit electrodes in the same planer and an electric field generated between a slit electrode layer and a plate electrode layer form a multi-dimensional electric field, which enables all liquid crystal molecules in all orientations between the slit electrodes and above the electrodes in a liquid crystal cell to rotate so as to enhance work efficiency of the liquid crystals and increase light transmittance. The Advanced Super Dimension Switch technology can improve the display quality of a TFT-LCD product, and is widely applied in the field of liquid crystal display due to the advantages of high resolution, high transmittance, low power consumption, wide viewing angle, high aperture ratio, low color aberration, no push Mura, etc.
The ADS mode display panel is formed by assembling an array substrate (i.e., TFT substrate) and a color filter substrate (i.e., CF substrate) and filling liquid crystals. Generally, gate lines (i.e., scan lines), data lines (i.e., signal lines), TFTs, via holes, pixel electrodes (i.e., display electrodes) and common electrodes are formed on the array substrate. In the array substrate, a plurality of gate lines and a plurality of data lines intersect to define a plurality of pixel units, one of the pixel electrode and the common electrode is a plate-shaped electrode and the other is a slit electrode, and the slit electrode is positioned above the plate-shaped electrode (the present invention is described by taking a case that the pixel electrodes are plate-shaped electrodes and the common electrodes are slit electrodes as an example). A black matrix (BM), RGB and the like are formed on the color filter substrate.
As shown in FIG. 1, the pixel electrode 3 is used for storing charges together with the gate line 2, the data line 1, the TFT and the via hole, and an electric filed is formed between the pixel electrode 3 and the common electrode 4 to drive the liquid crystal molecules between the array substrate and the color filter substrate to rotate, thus displaying different pictures. Specifically, when the gate lines 2 are scanned line by line, the data lines 1 sequentially charge the pixel electrodes 3 in the pixel units of the scanned row, after the scanning is finished, the pixel electrodes 3 in said row maintain the charged charges until said row is scanned again when displaying the next frame. The voltages of the data lines 1 vary continuously in one frame, so as to charge the pixel electrodes 3 in the respective rows.
As shown in FIGS. 1 and 2, to avoid capacitive coupling between a pixel electrode 3 and a data line 1, the pixel electrode 3 and the data line 1 are generally spaced apart from each other at a certain distance, and therefore, electric fields may be generated between the pixel electrode 3 and the data line 1 and between the common electrode 4 and the data line 1. However, since the distance between the pixel electrode 3 and the data line 1 is very small, the generated electric fields have little influence, but the electric field generated between the data line 1 and the slit-shaped common electrode 4 may result in that the liquid crystal molecules above and at both sides of the data line 1 cannot be rotated effectively. To solve this problem, in the prior art, a shielding electrode 5 (in fact, the shielding electrode is a part of the common electrode, but as the shielding electrode is provided above the data line to shield the data line, it is referred to as shielding electrode) is generally formed at a position corresponding to a data line 1 while forming the common electrode 4. The shielding electrode 5 and the common electrode 4 are applied with the same signal so as to shield the data line 1, so that an electric field is prevented from forming between the data line 1 and the common electrode 4, but meanwhile a relatively large capacitance is formed between the shielding electrode 5 and the data line 1. As a result, a data voltage signal on the data line 1 may affect a signal on the shielding electrode 5, which further causes a common electrode signal on the common electrode 4 to be disturbed and fluctuate wildly, resulting in defections of Greenish flicker, relatively large load and the like.